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LML CP4 Lawsuit

The cp4 lawsuit is only able due to social media and when so many people hear of the issue they band together - strength in numbers.

No doubt the ip replacement volumes which were mostly the pmd failures would have had its lawsuit(s) if we had the interconnectivity of modern times back then.

The issue that the cp4 design came about after the existence of non lubricant fuel should make it open and shut case, with one exception. Who says brand X shouldn’t be allowed to sell a poor performing product because they simply want to. Joke gum is sold that looks like a tasty treat yet can bring on vomiting in some. They have the right to sell what they want, at whatever quality they want and buyer beware.

There is a million ‘what ifs’ that GM could have done like better filtration, but it is their choice to raise the price of a truck to $250,000 to make it amazing, or cut corners where they choose.

‘Engine wear’ is the most common known long term issue and most that wear occurs at start up without oil pressure. A simple pre-oiler solves this and could be factory on every vehicle ever made. But no one mfr included it because it won’t make or brake the sale of the rig when it is new. So it has no marketing value. If 1 company did it for all their 2020 models and it did push their sales up taking sales from the competition, all mfrs would have it in their line by 2022. Then no advantage exists and all mfrs loose $ in the end. It’s like M.A.D. in the nuke arms race. They all know the outcome, so no-one acts first. Exceptional fuel filtering (or any filtering) is the same thing. GM might get but this one time over the cp4, but this is one of thousands of gambles made.

People driving with wif light on is their own fault. Correct on “can’t fix stupid”.
People drive when temp gauge shows overheating. People driving with a brake warning light on. But to be fair, individuals have to make the judgment when to push their luck. Improvements could be made by yellow vs red indicating lights. But you still should leave the end decision to to driver. I know when my 6.5 is at 250f I am ruining the engine, but if I am driving someone to a hospital who is minutes from death- I choose person over engine.
Same thing of sacrifice fuel system that some water just got sucked up from tank and an engine forced off as engine safety but maybe I am in heavy traffic and need to get out of traffic before stopping. Like why is lift pump on factory vehicle flow on fail vs aftermarket engine dies? Safety of driver and other surrounding cars.

My fix is I want audible danger buzzer and separate danger light when I my rig overheats, low coolant level, low oil pressure, low oil level, low fuel pressure. Because even though I try to be attentive failures can be instant.
Because of power steering and power brakes, I consider adding electric backup to the p/s pump like older hd trucks had so can be safer getting out of freeway traffic on engine failure. But that doesn’t mean GM, or AM General was wrong for not including it.
 
Brother we need to expand on this some. This exact "Stupid" is a reason the Olds 5.7 diesel was a complete failure, but, it's NOT just the operator/driver's fault here. First there is a complete lack of driver training what-so-ever nevermind RTFM to a specific vehicle and "stop the vehicle and tow it when a red light comes on". We read stories of someone bitching all the time that they couldn't get over 25 MPH with a blown transmission on a freeway with their kids in the car and they complain about all the other drivers waving without all fingers extended. Not one second of thought to get their busted ass vehicle off the road and tow it is shown in these stories. GM knew this and decided to skip WIF lights on the first of Olds 5.7 era (A recall was issued to add a WIF light!) and most OEM's skipped good diesel filters even into the late 2000's like Tractor Trailers have had forever.

Second the Goverment doesn't want drivers stalling out and clogging the roadways. They would like the driver to decide when it's safe to get off the road thus: engine and injection system expendable. You can't as an OEM "save the operator from their own stupidity" this could be done, but is illegal, by using water blocking filters linked below. As the filter absorbs water, the water absorbing material will swell, blocking the flow. The engine shutting down from a water blocked filter is unacceptable. The engine must be completely destroyed before stopping... and even then loss of power engine failure for other reasons can trigger a recall.

https://fil-trek.com/product/aquasorb-series/

Some use these water blocking filters between a in-bed aux tank and the main tank. HAHA a CP4 may still die from vapor lock "air" instead of water if a filter like this was used...

Bad fuel is out there. And at the end of the day there is dammed little the average owner can do about it.

I get ignored WIF lights. But you did leave off how unreliable the dammed WIF system is. By the time (if) the light comes on it's too late as damage is being done or is complete. Further consiteration is due to how much more water Biodiesel concentrations can suspend in the fuel vs. non-biodiesel laced diesel. For example "wet" Biodiesel, B99, I had wasn't triggering a WIF light. Adding #2 diesel to bring the concentration down to less than B50 immediataly triggered a WIF light. I am pissing in the ocean shareing the downsides of Biodiesel, however, it may educate some who are attempting to solve water or bugs in fuel problems and don't understand the biodiesel "X" factor of adsorbing and suspending way more water than normal #2 diesel. LSD and ULSD also suspend more water than old school diesel.

I'm not sure what vehicles you have experience working on. But I rarely see issues with WIF systems on light and medium duty diesels. They work how they should and the very small amount of water needed to turn on the light never makes it through the system as its trapped in the filter. If the light comes on we service the filters, open the drain plug on the lift pump (fords) and away they go. The only time I see issues is when someone ignores the light for to long. I've installed plenty of complete fuel systems over my career for people simply not servicing the truck when the light comes on. And sometimes the sensor requires replacing if it sat in water too long. But once again that's operator error. The way I see is WIF systems work great.

As far as the cp4 goes. It was never designed to run on our LSD fuel. No matter what you do they are a ticking time bomb. It also doesn't help GM didn't put a lift pump on the duramax till the l5p
 
Here in the heart of midwest farm country soy oil B5-B20 is almost a given at anywhere you fuel up and THAT has everything to do with fuel system longevity because Soy oil is great for lubricity. Yeah I know, I get flamed with "but what about the bug growth... o me-o my..." but that simply has been a near zero issue in my neck of the country. I do use Power Service in most tankfulls as well. 345,000+ miles on an entirely stock fuel system doesn't lie as I see it and there are plenty of others in the midwestern states that would tell you the same tale... Oh, and also, I haven't used a WIF sensor on my Parker/Racor fuel filters in well over 200k. Filter changed every 15k.
 
I removed the OEM fuel filter and use CAT tall spin on cans. 1 in rear, going through 2 lift pumps, then to the cat can up on the motor where the OEM filter used to be. I change both once yearly.
I use fuel supplement at every fill up. I do occasionally run B99 throughout the summer.
I have 176k on the 2006 Dmax...👍

Never any signs of WIF at all...
 
The soy vs corn is slightly better, but once both at 8%, they have both maxed out how much lube they add. But when compared to sulfur as a bonding agent- its about like using water as a lube instead of oil. Yes wet is less friction than dry, but not even in the same ballpark.

How much the sulfur helps? Figure the average in a tire is 1.6% by mass. The sulfur is what makes the tire flexible. Without it as a lube in the tire it will get hard and crack out in no time. Brand x vs y tire that one dry rots easy and fast vs the other lasting years perfectly can be 0.01% more by mass if all other components are the same.

When doing the plastics to fuel company testing, we ran different tire shreddings to see comparison levels and was looking for future options in other markets like shipping and that were not yet regulated. It is amazing how much lubricity we lost going to ulsd over old #2. The difference can not be made up in bio fuel, plain and simple.

The lubricity of fuel made from tires is insane. Zombie apocalypse happens, and I have to make my engines last for ever and need to make fuel- definitely using pyrolysis of tires- well that and zombie bodies! haha

Years ago here in southern Nv, in working with one of the biggest fuel suppliers (only 2 companies supply 95% here) when they were testing different biofuels paid by gubmint contracts for the prelim tests- they had to replace every engine in the public bussing system because of the horrible outcome of peanut oil bio. I was able to convince them of running a water plugging filter system that stopped flow completely. It didn’t hurt them having gubmint testing status at the time. Same idea as the filters WarWagon mentioned. They were on joint investigation with the other large fuel supplier here, and so when one company added them, so did the other. The filters are in the draw from the underground tanks, not at the plant. So end result is almost no one here ever gets any water in their fuel unless they get it in their themselves. The fact that we have almost no rain here helps tremendously too.

Most water gets into diesel fuel at the station. Next time you see a tanker doing a delivery, go look how the covers are sealed. It is easy to see how water gets in there. Also look for the air supply vents to the tanks, and pay attention to your humidity, and barometric levels. Some gas stations invest in water traps, some don’t.

What ever the local fueling stations are doing for water prevention is what determines your level of issues. If you hear of people in your area having problems- gear yourself up. If no one around you ever has issues, the local suppliers are in long term price wars and won’t invest in water prevention. The one company used to supply lower half of Nv, and Northern half of Az. They looked at going closer into Phoenix, but the competition there does so little in quality control that to be competitive, they would have to do the same. But that would have removed their testing status required quality levels, so they stayed out of that area. So unfortunately for folks like WarWagon, he gets worse fuel in his area for a savings of .02 per gallon. Here the investment paid itself off a decade ago and the price difference is gone.

I’ve mentioned before- if I lived where water contamination is a possibility, or if they stop using the water stopping filters at our stations, I will invest in one myself. That is even if I have to fill up into a barrel at the store, then pump it through a filtering system into a barrel on the ground. Then fill up from that. At that point I would probably just go back to what I did years ago and just run wmo centrifuged and cut with gas.
If I had a pickup with all the room underneath and that was the only diesel I owned, then I would just install the setup under the truck. Hummers simply don’t have the space to fit one.

When this was brought up before- the Mr funnel got brought up. A 5 micron filter supposed to separate water from fuel. Better than nothing- but water molecules are smaller than 5 microns unlike what they advertise. When you have any ethanol/methonal, it suspends the water in the fuel at a level of less than 0.5 micron. So pouring just water in the funnel it works great. But when actually in the fuel already- nope. Better than nothing I suppose, but I dont own one.
 
ALL DURAMAX diesel's use a lift pump, it just happens to be gear driven prior to the L5P(with the exception of the van's prime pump). GM had such a bad taste from the 6.2/6.5 electric lift pump failures they resisted using electric lift pumps until they had to. The biggest problem I see is the crappy fuel were stuck with here in the states. Look at the LB7, that same fuel system ran with very little trouble overseas, but the VCO nozzles proved to be problematic to say the least here in the states. The same with the CP4. We have a far higher failure rate here in the states than they do overseas, and last I checked there fuel standards were quite a bit better than ours as far as cetane and sulphur ppm.
 
I'm not sure what vehicles you have experience working on. But I rarely see issues with WIF systems on light and medium duty diesels. They work how they should and the very small amount of water needed to turn on the light never makes it through the system as its trapped in the filter. If the light comes on we service the filters, open the drain plug on the lift pump (fords) and away they go. The only time I see issues is when someone ignores the light for to long. I've installed plenty of complete fuel systems over my career for people simply not servicing the truck when the light comes on. And sometimes the sensor requires replacing if it sat in water too long. But once again that's operator error. The way I see is WIF systems work great.

As far as the cp4 goes. It was never designed to run on our LSD fuel. No matter what you do they are a ticking time bomb. It also doesn't help GM didn't put a lift pump on the duramax till the l5p

It's just my way of saying the water separators are not doing a good enough job for the WET and Dirty diesel we have and have had in The USA. Because by the time the WIF light comes on it's too late. Silly OEM's... diesel in the USA hardly meets specs. That's why Tractor Trailers have, and have had, massive fuel filters and separate massive water separators on them.

If the all in one OEM water separators were stopping the water you wouldn't be replacing fuel systems. Drove it too long?! What, the separators (all in one filter water separator) have an expiration date where they suddenly let the water by after magically blocking it so well? Not hardly: they are simply not stopping enough water in the first place. By the time there is enough water knocked out of the fuel to trip the light the entire fuel system has eaten plenty of water. Maybe they get lucky and get a big enough slug of water that the WIF light can turn on instantly so they might be able to stop the engine before the damage occurs.

Seriously the sub par filtration and several fuel filter redesigns due to injector failures for the Duramax alone is enough to realize OEM filters were gambled on too cheap to do the job.

So it's not that the WIF sensor is defective in design per say it's the separator filter not doing a good enough job in the first place to knock enough water out to trip the sensor.

Then there is the defective sensor generating a nuisance WIF light, WIF sensor falling out of the Krap plastic body WIX Duramax fuel filter or leaking air. Ask the AZ DOT about how many Duramax powered things they had towed to the dealer due to plastic body WIX fuel filters WIF sensor falling out or WIF sensor threads leaking air.

Some fuel filters made and on the market today for the 6.5TD doesn't even meet the antique "bolder sized" micron spec of yesterday.

As far as biodiesel goes I merely point out what most don't know about it. Running B20 requires a better water separator. Old School Cummins engines for government use that could handle 20% biodiesel vs. 5% on the street had one major difference: an additional water separator. Those who never have had trouble with bad fuel: LUCKY YOU. However, "So what?" as clearly there is bad fuel out there. Further Diesel fuel is changing not only ULSD but addition of an ever increasing level of Biodiesel.

With DEF on the market and in use we now also get to watch DEF dumped in the fuel tank failures. IMO putting the two fill holes under a single fuel door like some pickups have is bad design. Like the bad industrial design that melted 3 Mile Island Down. Did I mention the section of the owner's manual where fuel quality is on you and by that I mean You, your fuel supplier, and insurance company. Save your fuel receipts.

The 6.5 fuel system I put a CAT water separator on, well, it lived when the bad wet fuel arrived. The other 6.5 fuel system fed out of the same fuel tote with the OEM filter only: didn't. No WIF light until it was way too late. (Again when #2 diesel from a station was added it knocked enough water out that the light finally tripped.) Governor parts out of the failed IP below. Yes that was replace: tank, lift pump, IP, injector lines, and injectors.

93_IP_ate_by_biodiesel_bugs.jpg
 
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Good point...
Deep pocket theory...
Lawyers.
Yep, it's all about who has the deepest pockets. I think GM is being targeted since they abandoned the CP4 and BOSCH and went with DELPHI. So they're looking at it as admission of guilt. FORD is still using the CP4 and CUMMINS just switched, so the ramifications of this could get interesting if anything comes of it.
 
Are the Delphi systems fairing any better? Or is it still too early to tell?
So far they ate fairing quite well. Delphi stayed with the time tested CP3 design of 1 cam, 1 cam lobe, and 3 pumping plungers instead of the CP4.2 design of 1 cam, 2 cam lobes, and only 2 pumping plungers. The injectors are of the time tested & proven solenoid type instead of piezo crystals and super high AC voltage. It's essentially very similar to the LBZ/LMM system, just further refined(hence how people put LBZ ECM's on L5P's & ran them).
 
If The cp4 isn’t a GM creation, should the third party should eat the issues because just like the people buying the truck had reasonable expectation of proper operation- so would GM

No. Buyer beware. GM should have tested the CP4 "to failure". Instead it's typical GM of attempting to do Diesel as cheap as possible and "To hell with the reputation." GM beancounters looked at the cheaper part and ran with it. Further I am sure GM attempted to force the supplier to reduce the cost even further after the ink was dry on the contract in typical GM fashion. Dammit, CP4 lawsuit... We gotta run another ad showing a "running" Duramax towing something... :woot:

Only because warranty and working hard to deny warranty cost so much did they switch to something else. You as the #1 VOLUME dealer in the state of CA are NOT going to tell one of your largest fleet buyers a lie about fuel causing it esp. if they happen to work in the Oil industry. Yes, the fleet manager will send a sample of the fuel out the second time... In fact said fleet GM dealer may be extending "Goodwill" coverage even if the time and or miles is slightly out of warranty. No Sir, we covered it: the transmission should not have broke a band at 37K miles on your fleet pickup. Now the R4 compressor on your personnel Yukon, well, we asked the area rep to look at it and you are S.O.L.

You would think the OEM's would get the damn picture by now of the actual fuel quality in The USA vs. some wet dream of a spec that a typical low bidder gas station owner isn't meeting.

How many people go out of their way to save one cent on fuel? Just saying...

Some examples of OEM's finally getting it are: plastic fuel tanks that don't corrode or otherwise provide particles to ruin a fuel system, 2 fuel filters standard on late model Cummins powered pickups, and verbiage in the owner's manual that fuel quality is on YOU.
 
No. Buyer beware. GM should have tested the CP4 "to failure". Instead it's typical GM of attempting to do Diesel as cheap as possible and "To hell with the reputation." GM beancounters looked at the cheaper part and ran with it. Further I am sure GM attempted to force the supplier to reduce the cost even further after the ink was dry on the contract in typical GM fashion. Dammit, CP4 lawsuit... We gotta run another ad showing a "running" Duramax towing something... :woot:

Only because warranty and working hard to deny warranty cost so much did they switch to something else. You as the #1 VOLUME dealer in the state of CA are NOT going to tell one of your largest fleet buyers a lie about fuel causing it esp. if they happen to work in the Oil industry. Yes, the fleet manager will send a sample of the fuel out the second time... In fact said fleet GM dealer may be extending "Goodwill" coverage even if the time and or miles is slightly out of warranty. No Sir, we covered it: the transmission should not have broke a band at 37K miles on your fleet pickup. Now the R4 compressor on your personnel Yukon, well, we asked the area rep to look at it and you are S.O.L.

You would think the OEM's would get the damn picture by now of the actual fuel quality in The USA vs. some wet dream of a spec that a typical low bidder gas station owner isn't meeting.

How many people go out of their way to save one cent on fuel? Just saying...

Some examples of OEM's finally getting it are: plastic fuel tanks that don't corrode or otherwise provide particles to ruin a fuel system, 2 fuel filters standard on late model Cummins powered pickups, and verbiage in the owner's manual that fuel quality is on YOU.
Well, Ford used the SAME CP4 on the 6.7l. The only real difference was GM used a gear driven supply pump and Ford used an electric. And Cummins is now using that same CP4 pump as of 2020. So maybe GM used what they were told was tested by the biggest name in diesel fuel injection, and would work on US diesel. This issue cannot be blamed on GM because they used dual filtration that filters to well under Bosch's requirements, used nothing but Bosch right down to the ECU to fire them, and went above the other's to ensure only stock tuning would be ran(yes, many got around it, but GM used the best means available of any manufacturer). You list off problems from 15+ years before the CP4 was used, so maybe GM did all they could in this instant, but the lawyers are just going after the deepest pocket.
 
Well, Ford used the SAME CP4 on the 6.7l. The only real difference was GM used a gear driven supply pump and Ford used an electric. And Cummins is now using that same CP4 pump as of 2020. So maybe GM used what they were told was tested by the biggest name in diesel fuel injection, and would work on US diesel. This issue cannot be blamed on GM because they used dual filtration that filters to well under Bosch's requirements, used nothing but Bosch right down to the ECU to fire them, and went above the other's to ensure only stock tuning would be ran(yes, many got around it, but GM used the best means available of any manufacturer). You list off problems from 15+ years before the CP4 was used, so maybe GM did all they could in this instant, but the lawyers are just going after the deepest pocket.

First off knowing GM "went away from" the CP4 to the CP3 equivalent is actually news to me and I concede that point of GM going to something better than a CP4. I would have considered a new Duramax a little closer had I known this except I am burned on GM's diesel and "other" reputation too much at this point. However we both know the CP4 is "value engineered" cheaper than a CP3 and that is something that OEM's Bean Counters have a hard time resisting. Case in point is Cummins avoided the CP4 till 2019. So there was no CP4 switch and then "Ewww.... Warranty is expensive! Find something else!" I voted with my money to avoid a CP4 and got a 2018 not a 2019. I think it's a mistake for Cummins to go to the CP4 no matter what "lipstick" improvements Bosch claims to have applied to the pig. Time will tell, but, reputation and history doesn't make for good odds.

Other OEM's went to an in-tank lift pump ... GM aparentally couldn't get anything but a cheap sub $50.00 6.5 style lift pump past the bean counters. So yeah: why bother. Aftermarket lift pumps and filters that sell for $500 sell well for a reason. Diesel fuel here in the USA is the same "low quality" with only Biodiesel and ULSD changing the water content. 15+ years problems are still here today. Yes, I have held a belt driven lift-pump in my hands for install on the Cummins ride because of overall lift pump troubles. GM's in tank fuel pumps weren't exactly reliable at one time for the gas rigs.

You couldn't give me a "meet emissions requirements early" Cummins powered RAM pickup from 2007.5 till they started using the DEF systems of 2013.

Bosch is not exactally a good reputation with GM having to extend the warranty on the early HPCR injectors. Cummins had trouble with the early 2003+ Bosch injectors... And who is the company that intentionally mis-applied the word "NEW" to their krap that contained a "USED" injector body? Shopping for a new set of "expensive: HPCR injectors is a genuine s#it show as everyone wants to deliver you reman injectors. Ask me about their name being smeared on junk Oil Filters...

End of the day it's a Bowtie or "GMC" on the tailgate and ultimately GM's responsibility to choose who builds what for their engines.

One thing has changed: TCO. Hard to find "economy" in a (pickup automotive) modern diesel anymore due to higher fuel cost, initial sticker shock cost, and maintenance costs.
 
This is interesting.
View attachment 57815


I was concerned enough about the CP4 issue, having read so many forum posts on the subject, that I contacted Morgan and Morgan about the class action lawsuit. I don't know what the current situation is, but for those who have experienced a CP4 failure, it might be worth giving their office a call.
 
I was concerned enough about the CP4 issue, having read so many forum posts on the subject, that I contacted Morgan and Morgan about the class action lawsuit. I don't know what the current situation is, but for those who have experienced a CP4 failure, it might be worth giving their office a call.
Morgan & Morgan is a bunch of slime balls only in it for themselves. Trust me, they will screw ANYBODY over for a buck.
 
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